1. Field of the Invention
The present invention relates to a reproducing system for mediums and a method for reproducing digital data and identifying the same.
2. Description of the Related Art
Digital storage of data has been in use for decades. Usually, digital data are stored in different types of storage mediums, such as MO (magnetic optical) discs, CDs (compact discs), LDs (laser discs), DVDs (digital versatile discs) or BDs (blue ray discs). Due to the development of different types of computers, the specifications of the mediums have to comply with the different generations of computers. The various mediums employ different compression technologies, so different types of mediums can store different amounts of digital data.
Most digital storage mediums are made for storing digital data that is read-only. The users may need to re-store their digital data in a new medium to make them editable. Furthermore, almost every medium has limitations on its lifetime. When digital data is stored in a medium for longer than the lifetime, the digital data may become unreadable. As a result, users need to periodically re-store their digital data in a new medium to avoid data loss.
In order to save space, users may wish to use a disk with better compression to replace the old one when re-storing the digital data. For example, generally, one BD can store more than 25 GB of digital data, while one DVD can store 5 GB digital data. Thus, the user may want to use one BD to replace five DVDs when re-storing the data.
After re-writing the digital data into alternative mediums, users may not be able to identify the content of the mediums from the outward appearance of the mediums. Thus, traditionally, it is required to have a label attached on the surface of a medium for users to identify the content of the medium. However, if a user needs to backup his/her digital data by re-storing it into a new medium, the user may need a label printer to apply a label on the surface of the medium. Often, the description on the label, which is very short, has a limited amount of information. If the user needs an index to show the digital data content and the corresponding label, he/she has to build such an index manually.
Normally, the index was saved automatically into a computer that processes the writing of the digital data. However, when the user may want to know a content of a specific batch processed mediums. In other word, the user may want to know a total index of the digital data in each medium after writing so as to identify the mediums.
Therefore, there is a need to provide a reproducing system for mediums and a method for reproducing digital data and identifying the same.